Method and device for separating the skull and the vertebral column of a slaughtered animal

Abstract: The invention relates to a method for processing the neck of a slaughtered animal such that the skull is separated from the vertebral column, which method comprises the steps of: (1) positioning a slaughtered animal for processing; (2) providing a separating device (16,17,18), for instance a hydraulically or pneumatically energized pair of scissors, to arrange a separation in the cervical vertebral column, for instance between the skull and the first cervical vertebra; (3) determining the location where the separation must take place; and (4) positioning the separating device (16,17,18) and activating same on the basis of the result of step (3) in order to arrange the separation.

Description: The invention relates to a method as defined in the precharacterizing portion of claim 1. The invention also relates to a device for performing such method, the device being defined in precharacterizing portion of claim 2. Such a method and device are known from EP-A-0 212 580. Usual is substantially vertical positioning of the animal, for instance suspended from the hind legs. Using a hydraulically or pneumatically energized scissor tool the neck of the animal, for instance a pig, is cut through. This processing method has the drawback of being none too accurate. It can occur that due to the separating operation bone splinters are separated from the locally present bones, which is undesired. Loss of usable meat can also occur due to the inaccuracy of the cutting operation. The separating operation takes place in the vertebral column, for example in the region between the occipital protuberances and the atlas, or further to the rear in the direction of the tail. The object of the invention is to perform the separating operation with higher accuracy, such that the occurrence of bone splinters is effectively prevented, while the danger of usable meat being lost is also considerably reduced. The method according to the invention is characterized for this purpose by the characterizing feature (e) of claim 1. The rear surface is not always flat but has different shapes depending on the type of animal. The separating device can for instance be adapted to follow the shape of this rear surface. It is noted that a separation between cervical vertebrae can also take place. The device according to the invention is characterized for this purpose by the characterizing features of claim 2. In EP-A-0 212 580 the scissors form part of rough means of bringing the separating device to a cutting position by moving the scissors in its opened or rest-position downward until an electrical switch senses an increased mechanical movement resistance. This detection triggers the scissors drive to stop, thus determining the operative separating position of the scissors. In this specification EP-A-0 212 580 also the possibility of using measuring means separate from the separating means is disclosed. Use is made of a measurement of the lowermost zone of the head of the animal, i.e. the nose. From this per se already rather rough approximation on basis of statistical information furthermore the nominal cutting position is derived on a statistical basis. This whole measuring method is highly inaccurate. Contrary to this rough approximation the invention actually performs a measurement of a previously chosen position in the bony structure of the slaughtered animal and on basis of this measurement controls the adjustment of the scissors to bring same to its operative separating position. According to the invention, therefore, the measuring device is separate from the separating device. It is noted that AU-B-22723/88 discloses a neck breaker machine and method. This machine comprises a mounting arrangement adapted such that the neck of an animal carcass can be located and retained between engagement members. This prior art reference is not concerned with a separating operation, let alone such an operation that has to be performed with the highest possible accuracy. The measurement of the position of the transition between the skull and the first cervical vertebra can, in accord with the teachings of the present invention, take place in diverse ways. Use can for instance be made of a video camera having signal processing means coupled thereto. The camera determines for example the position of the ears, while the signal processing means processing the video signals determine the cutting position, for instance partly on the basis of a statistical correction, wherein between the implant of the ears and the cutting position a distance of for instance about 50 mm is chosen. The drawback to cameras with the associated electronic processing is that they are expensive and vulnerable and operate less accurately. A mechanical scanning to determine the position of the ears and/or the tip of the nose is also possible. The separating position is derived from the result of this scan. A direct rather than an indirect measurement is therefore recommended according to the invention. This can particularly take the form of a hard detection. A device utilizing this principle has the feature that the measuring device comprises a pointed pin which can be placed through the soft tissue to come into contact with the rear surface of the skull oriented toward the vertebral column. A further development of this principle is embodied in a device having the feature that the measuring device comprises a second pointed pin which can be placed through the soft tissue to come into contact with the rear surface of the skull oriented toward the vertebral column, which second pin is placed at a distance from the first pin such that the measuring device can also determine the angle at which the rear surface of the skull extends for corresponding control of the positioning device coupled to the separating device. A device of the above described type operating with at least one pin preferably has means for retracting the pin(s) prior to activating of the separating device. Insertion of the pin or pins into the animal can result in a certain change in position or wobbling, which can make the separating operation difficult. In this respect the device preferably has the feature that the positioning means comprise a support which prevents movement of an animal under the influence of the pin(s). It has been found in practice that the use of one pin usually provides a sufficiently high precision of the separating operation. This is even the case when the separation takes place along the rear surface of the skull. For successive slaughtering of animals of one particular category the position of this surface will generally be the same within the set tolerance limits. The use of two pins can have the advantage that herewith a positive indication is obtained as to the spatial position of the rear surface. This may contribute to the accuracy of the separating operation. It is possibly advantageous if the at least one pin extends at least roughly in the plane of symmetry of the animal. A particular variant has the special feature that the separating means also serve as support. As an example hereof reference can be made to the use of a pair of scissors which is placed by a limited energizing against the relevant zone of the neck of the animal, whereby swivelling is prevented. After the desired cutting position has been determined, a definitive positioning of the scissors optionally takes place followed by energizing to perform the separating operation. In addition to the above mentioned principles of video detection and direct hard detection, the measuring device can also be based on ultrasonically operating means or on means based on X-rays. With regard to the separating operation it is noted that use is usually made of an energized scissor tool. Other suitable separating means can also be considered such as cutting, sawing, the use of a rotary knife, a vibrating knife, and infrared laser etc. In a variant the device has the feature that the separating device comprises an endless drivable wire. Such a wire, which in its active part has a sufficiently high tensile stress, has the advantage of cutting easily through relatively soft tissue but not cutting through bone. The invention will now be further elucidated with reference to the annexed drawings. Herein: figure 1 shows partly in side view, partly in section a separating device according to the invention during processing of a slaughtered pig; figure 2 shows a partly broken away perspective view of the device of figure 1 on enlarged scale. Figure 1 shows a pig 1 which is suspended from its hind legs 2 by means of hooks 3. These hooks are displaceable over a rail 5 by means of a suspension bracket 4. In this manner the pig 1 is positioned relative to a measuring and separating device 6. This comprises a frame 7 (see also the detail drawing in figure 2), the angular position of which is adjustable as according to arrow 8 by rotation round the rotation axis of rotation bearings 9, 10. The frame is vertically displaceable along pillars 11, 12 as according to arrow 13. The longitudinal position of the lower arm 14 of frame 7 is adjustable. This arm supports two blades 16, 17 which are driven by a pneumatic cylinder 15 and which can swing relative to arm 14 by means of a hinge 18 and which together form a pair of scissors 16, 17, 18. The frame 17 carries two obliquely disposed pneumatic cylinders 19, 20. The associated respective piston rods 21, 22 are embodied as pointed pins which can be inserted through the soft tissue of the neck of the pig 1 to be subsequently blocked against further movement by the rear surface 23 of the skull 24. Figure 1 in particular shows the actual shape of this rear surface. Clearly shown are the so-called occipital protuberances which, in some animals, particularly sheep, are more pronounced. The pointed ends 25, 26 of piston rods 21, 22 lie roughly in the median plane of the pig and the effective cutting plane of scissors 16, 17, 18 extends substantially through the connecting line of the ends 25, 26. It will be apparent that this ensures that the cutting action takes place in this plane in which the attachment between the skull and the first cervical vertebra is situated. The intended separation therefore takes place in this plane. It will be apparent that the position and spatial orientation of the rear surface 23 are determined through the use of the two pins. Once the desired position of the scissors 16, 17, 18 has been determined in relation to the surface 23, the piston rods 21, 22 can be retracted at least over some distance by relevant energizing of cylinders 19, 20, whereby the action of scissors 16, 17 is not impeded. Displacing of the blades 16, 17 toward each other takes place by appropriate energizing of cylinder 15. The housing of cylinder 15 is hingedly connected to the blade 16 in the manner shown in figure 2, while the piston rod of cylinder 15 is hingedly connected to arm 17. In this embodiment the cylinder 15 can be freely positioned in space, that is, the free end not visible in figure 2 is not connected to any part of the device.

Claims: Method for processing the neck of a slaughtered animal such that the skull is separated from the vertebral column, which method comprises the steps of: (a) positioning a slaughtered animal (1) for processing; (b) providing a separating device, for instance a hydraulically or pneumatically energized pair of scissors (15-17), to arrange a separation in the cervical vertebral column, for instance between the skull (24) and the first cervical vertebra; (c) determining the location where the separation must take place; and (d) positioning the separating device (15, 16, 17) and activating same on the basis of the result of step (c) in order to arrange the separation, characterized by (e) performing step (c) such that the desired separating position is determined by means of a measuring device (21, 22) by measuring directly at least one point of the rear surface of the skull (24), said measuring device (21, 22) being separate from the separating device (15, 16, 17). Device (3-14) for performing the method according to claim 1 for processing the neck of a slaughtered animal (1) such that a separation is arranged in the vertebral column, which device comprises: positioning means (3-5) for positioning a slaughtered animal (1) for processing; and a separating device, for instance a hydraulically or pneumatically energized pair of scissors (15-17), for arranging a separation in the cervical vertebral column, for instance between the skull (24) and the first cervical vertebra, characterized by a measuring device (21, 22) which is separate from the separating device for measuring directly at least one point of the rear surface of the skull (24), and for thus determining the desired separating position, for example the transition between the skull (24) and the first cervical vertebra; and a positioning device (7, 14) which is coupled to the separating device and which, under the control of the measuring device (21, 22), positions the separating device such that when activated the latter arranges said separation. Device as claimed in claim 2, characterized in that the measuring device comprises a pointed pin (21) which can be placed through the soft tissue to come into contact with the rear surface of the skull (24) oriented toward the vertebral column. Device as claimed in claim 3, characterized in that the measuring device comprises a second pointed pin (22) which can be placed through the soft tissue to come into contact with the rear surface of the skull (24) oriented toward the vertebral column, which second pin (22) is placed at a distance from the first pin (21) such that the measuring device can also determine the angle at which the rear surface of the skull (24) extends for corresponding control of the positioning device (7, 14) coupled to the separating device. Device as claimed in claim 3 or 4, characterized by means (19, 20) for retracting the pin(s) (21, 22) prior to activating of the separating device. Device as claimed in claim 3 or 4, characterized in that the positioning means (3-5) comprise a support which prevents movement of an animal under the influence of the pin(s). Device as claimed in claim 6, characterized in that the separating means also serve as support. Device as claimed in claim 2, characterized in that the measuring device comprises ultrasonically operating means. Device as claimed in claim 2, characterized in that the measuring device comprises means based on X-rays. Device as claimed in claim 2, characterized in that the separating device comprises an endless drivable wire.

Inventors: VAN OCHTEN SANDER ANTONIE, VAN OCHTEN, SANDER ANTONIE
Applicants: STORK RMS BV, STORK R.M.S. B.V.
Application year: 1994
Main classification: A22B5
IPC codes: A22B5